Roller leveler machine



Dec. 20, 1938. E. B. FERNBERG ROLLER LEVELER MACHINE Filed April 5, 1954 2 Sheets-Sheet 1 [NI/ENTOR Ema B1 RUEKZ PERNBERCI.

Dec. 29, 1938. E FERNBERG 2,141,151

ROLLER LEVELER MACHINE Filed April 3, 1934 '2 Sheets-Sheet 2 5 INVENTOR E 91c 151mm PERNBERCT.

ATTORNE Y Patented Dec. 20, 1938 NITED STATES PATENT OFFICE to- The Edward G. Budd Mandi pony, Philadelphia, Pa, a corporation of Pennsylvania Application April 3, 1934, Serial No. 718,754

In Great Britain April 28, 1933 7 Claims. (CL 153-54) This invention relates to amachine employed in the sheet metal industry and known generally as a roller leveler machine for the cold working of metal sheets.

5 It is essential, in the treatment of metal shee which are to be used ultimately in deep drawing and complex forming operations, to eliminate as far as possible what are known as stretcher strains, and this has been achieved by passingthe 10 sheets individually through a roller leveler machine in which they are subjected to a bending and subsequent straightening operation.

Machines for this purpose have been proposed and used with success, although they have not 16 attained all the desiderata thought to be necessary in the cold working of metal sheets. Such machines comprise a series of rolls through which the sheets are passed after being subjected to a bending operation over a roll which is caused to 20 move automatically out of the plane of the straightening rolls either by electrical means, controlled through the body of the sheets or by pneumatic means operable when the sheet is first gripped by the pinch or leading rolls.

25 Machines of this type are described in-theprior U. S. Patents Nos. 1,649,704; 1,649,705 and 1,649,706, all dated November 15, 1927 and 1,855,709, dated April 26, 1932. i

In order to obtain the most satisfactory results, in which the sheets so cold-worked may be drawn and formed with facility and without wrinkling and other defects, it is desirable to produce a sharp bend and to effect the bending operation rapidly. The former of these is gov- 35 erned by the diameter of the rolls and the latter by the surface speed of the rolls and both of these characteristics are in turn governed, in the existing machines, by the mechanical design. If the diameter of, or the surface speed of, the

40 rolls be decreased or increased respectively or if both be changed in the desired direction there will be a tendency of the rolls to whip. This must be avoided.

Now it is the object of the present invention to 45 provide a machine in which both of these desirable characteristics, viz. reduction of diameter of the rolls and increased surface speed are attained a plurality of bearing blocks carried by opposed and staggered beams, the one fixed and the other movable under the control of the sheet in any well-known manner.

Preferably the roller or ball bearings are ar- 5 ranged close together so that their peripheries present, as nearly as possible, a continuous cylindrical surface.

0n account of the avoidance of whip of the beams, it is possible to increase their length and thereby to treat wider s'heets than has been possible hitherto, whilst with the present construction, to attain still greater rigidity, the beams may be increased in depth.

It has been propesed, in connection with the treatment of wide metal sheets and in order to avoid whip of the beams, to provide extra bearings at points intermediate the ends of the beams, but this method does not give sharper bends to, nor more rapid treatment of, the sheets to be worked. I

As an example, will be described one form of the invention, reference being had to the accompanying drawings, Figure l of which is a side elevation, showing only those parts of the machine pertinent to the invention. Figure 2 is a part transverse elevation of the movable element and Figure 3 a part plan view with the main straightening rollers omitted for clarity.

On a suitable base frame (not shown) is mounted the roller leveler mechanism proper consisting of the upper and lower series of straightening rolls indicated at a and b between which the sheet 0 passes after being subjected to the bending operation at the front of the machine.

The rolls may be driven in any well known manner.

The lowerseries of rolls b may be supported in side frame members (not shown) secured to the base frame whilst the upper series a, arranged in staggered relation to the lower series in the direction in which the sheet 0 is fed through the machine, may be supported in a frame (not shown) mounted adjustably on the base frame to permit adjustment thereof in relation to the lower series of rolls.

Towards the front of the machine are mounted a pair of pinch or draft rolls d, adapted to grip the sheet to prevent it from slipping during the actual bending operation, which may be controlled either electrically through the body of the sheet when it is first gripped by the pinch rollers or by other means such as pneumaticor hydraulic, the

' spaced apart suiilciently to allow the actual bending mechanism to be mounted and to bemoved' upwardly therebetween. I

The bending mechanism proper comprises two transverse beams II and 12, the one I! mounted fixedly in association with the upp roll 6, and the other H mounted to be moved up and down in a vertical direction, between the hold-down and pinch rolls e and d, through the intermediary of the sheet, but normally being so disposed as not to interfere with the straight through pas sage of the sheet 0 until it is grippedlby the pinch rolls d.

Each of the transverse beams I I and It carries a plurality of bearing blocks l3, ll, secured by means of the bolts l5, which in turn support. a plurality of rollerand/or ball-bearings l6, arranged as close to one another as possible so that their peripheries present a substantially continuous cylindrical surface. The beams H and .I2 are arranged in opposition and in staggered relation longitudinally of the machine.

The outer surfaces of the roller or ball bearings are slightly crowned, like a fiat-belt pulley, as can be seen clearly in Figures 2 and 3, to avoid any possibility of scoring the sheets, with the sharp edges of the bearings, as they pass through the machine.

Although the beams I! and [2 are in staggered relationship longitudinally of the machine, it must be understood that the rolleror ball-bearing elements are in transverse alignment, as will be seen in Figure 3.

A sheet to be treated is fed to the machine first through the hold-down rolls e and straight through until it is gripped by the pinch rolls d, whereupon the control of the movable transverse beam H is actuated, in any well-known manner, to thrust the sheet upwardly and effect the bend, the sheet passing under .the series of rollerand/or ball-bearings carried in the fixed transverse beam |2 thereby ensuring equal bending first one way and then the other. To permit this operation the hold-down rolls e are allowed a small degree of slip. The sheet 0 continues on through the machine and is effectively straightened by the straightening rolls a, b.

To ensure aproper feeding of the sheet through the machine, suitable guide elements I I, I8 may be provided.

- The transverse beams II and I2 may be constructed of heavy section so that they will remain rigid under load and furthermore they may be increased in lengthand depth thereby enabling wider sheets to be treated, without introducing any tendency to whip, whilst the actual bending elements, 1. e. the balland/or roller-bearings l6 may be of much smaller diameter than is possible in the machines at present in use thereby giving greater surface speed of the bending rolls for equal operating speeds, whilst in some cases the speed of operation of the machine may be increased. I

. In this manner the advantages of sharper bending at increased speed are attained without a attendant disadvantages. 1

What I claim as my invention is:

1. A machine for treating metal sheets comprising spaced pairs of feeding rolls and means disposed to operate in the space between said feeding rolls to stress the sheet in its passage through the machine, said stressing means comprising two or more series of rollers and a vertically deep rigid support for each series, said series ofrollers being of relatively small diameter as compared with the diameter of the feed rolls and arranged when in operative position in staggered relation transversely of the machine whereby the sheet is given a plurality of sharp bends in its passage through the machine.

2. A machine for treating metal sheets comprising spaced pairs of. feeding rolls and means for stressing a sheet in its passage between said spaced feeding rolls, said means comprising several series of rollers arranged in staggered relation and closely spaced longitudinally of the machine, vertically deep rigid supports for said rollers extending through substantially the width of the machine, said rollers being of relatively small diameter as compared with the diameter of the feed rolls and said series being arranged I machine. a 3. A sheettreating machine of the class described comprising spaced pairs of feeding rolls and sheetstressing means disposed to operate in the space between said pairs of feeding rolls, said stressingmeans comprising at least two series of rollers arranged transversely of the machine, the rollers of each series being arranged in close proximity to present a substantially continuous cylindrical periphery or surface, a fixed support for one of said series and a movable support for the other of said series, whereby the'two series may be moved into staggered. relation transversely of the machine to bend the sheet about both series of rollers in its passage through the machine.

4. A machine for treating metal sheets comprising spaeedpairs of feeding rolls and sheet stressing means disposed to operate in the space between said pairs of feeding rolls, said stressing means comprising at leat two vertically deep rigid beams extending substantially from side to side of the machine and each carrying roller ,means said beams for supporting said roller means at longitudinally closely spaced points along the beams, said roller means being of relatively small diameter as compared with the diameter of the feed rolls and arranged when in operative position in staggered relation transversely of the machine, whereby the sheet is given a plurality of sharp bends in its passage through the machine.

5. A sheet treating machine adapted to operate on wide sheets comprising spaced pairs of sheet feeding rolls and means for stressing the metal of the sheet in its passage through the space between said pairs of rolls, the said means comprising at least one series of rollers of small diameter as compared with the diameter of the feed rolls arranged transversely to the direction of travel of the sheet and a vertically deep rigid support for said rollers, the rollers being arranged in close proximity and individually rotatablymounted on independent bearings disposed besent a substantially continuous cylindrical periphery or surface.

6. A machine for treating wide metal sheets comprising spaced pairs of feeding rolls and stressing means disposed to operate upon a sheet while passing between said pairs of feeding rolls, said stressing means comprising at least one series 'of rollers, and bearing blocks each having an extension narrower than the rollers extending between and supporting said rollers for individual rotation on independent bearings and in closely spaced relation to present a substantially c0ntinuous cylindrical periphery or surface, and a vertically deep rigid beam removably mounting said bearing blocks.

7. A sheet treating machine adapted to operate on wide sheets comprising spaced pairs of sheet feeding rolls and means for stressing the metal of the sheet in its passage through the space between said pairs of rolls, the said means comprising at least one series of slightly crowned rollers of small diameter as compared with the .diameter of the fed rolls arranged transversely to the direction of travel of the sheet and a vertically deep rigid support for said rollers, the rollers being arranged in close proximity and individually rotatably mounted on independent ERIC BIRGER FERNBERG. 

